\name{CreateGeometry}
\alias{CreateGeometry}
%- Also NEED an '\alias' for EACH other topic documented here.
\title{
Creates a geometry object
}
\encoding{UTF-8}
\description{
根据几何对象类型，创建几何对象
}
\usage{
CreateGeometry(geoType)
}
%- maybe also 'usage' for other objects documented here.
\arguments{
  \item{geoType}{
几何对象类型，支持“point”, "line", "region"。
}
}
\details{
%%  ~~ If necessary, more details than the description above ~~
}
\value{
创建成功，
如果是“point”，则返回\code{\link{GeoPoint-class}}对象;
如果是“line”，则返回\code{\link{GeoLine-class}}对象;
如果是“region”, 则返回\code{\link{GeoRegion-class}}对象;
失败返回NULL。
}
\references{
%% ~put references to the literature/web site here ~
}
\author{
%%  ~~who you are~~
}
\note{
%%  ~~further notes~~
}

%% ~Make other sections like Warning with \section{Warning }{....} ~

\seealso{
\code{\link{CreatePoint}}, \code{\link{CreateLine}}, \code{\link{CreateRegion}}, \code{\link{SetPoints}}
}
\examples{
geo.point <- CreateGeometry("point")
is.set.point <- SetPoints(geo.point, 10, 20)

geo.line <- CreateGeometry("line")
xs <- c(10,10,20,20,30)
ys <- c(20,40,40,60,90)
ps <- matrix(nrow=5, ncol=2)
ps[,1] <- xs
ps[,2] <- ys

is.set.line <- SetPoints(geo.line, ps, c(5))

geo.region <- CreateGeometry("region")
xs <- c(10,20,20,10,10)
ys <- c(20,20,10,10,20)
ps[,1] <- xs
ps[,2] <- ys
is.set.region <- SetPoints(geo.region, ps, c(5))

}
% Add one or more standard keywords, see file 'KEYWORDS' in the
% R documentation directory.
\keyword{supermap}
